BMI Changes Predictive of Bilateral Knee Pain in Women
Significant association between higher body mass index at year one and knee pain in year 15
FRIDAY, July 15 (HealthDay News) -- Changes in body mass index (BMI) are associated with year 15 (Y15) bilateral knee pain in women irrespective of radiographic knee osteoarthritis (RKOA) status, according to a study published online July 7 in Arthritis Care & Research.
Lyndsey M. Goulston, from the University of Southampton in the United Kingdom, and colleagues investigated changes in BMI over a 14 year period and its association with knee pain at Y15. BMI data from 594 females were collected from clinic visits at years one, five, 10, and 15. Details on Y15 knee pain were obtained by use of questionnaires.
The investigators found that BMI increased significantly from Y1 (median, 24.5 kg/m²) to Y15 (median, 26.5 kg/m²). Knee pain at Y15 was experienced by 45.1 percent of the women. Significant predictors of Y15 pain were greater BMI at Y1 (odds ratio [OR], 1.34), greater BMI at Y15 (OR, 1.34), and change in BMI over 15 years (OR, 1.40). The association between BMI change and knee pain was significant only in bilateral (OR, 1.61; 95 percent confidence interval [CI] 1.05 to 1.76), not unilateral knee pain (OR, 1.22; 95 percent CI 0.73 to 1.76) and was independent of RKOA. Follow-up measurements confirmed similar strength of association between Y15 knee pain and BMI.
"Over 14 years, a higher BMI predicts Y15 knee pain in women, independently of RKOA. When adjusted, the association was significant in bilateral, not unilateral, knee pain suggesting alternative pathological mechanisms may exist," the authors write.